package com.snailxr.base.listener;

import java.lang.reflect.Field;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.mongodb.core.FindAndModifyOptions;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener;
import org.springframework.data.mongodb.core.mapping.event.BeforeConvertEvent;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.core.query.Update;
import org.springframework.util.ReflectionUtils;

import com.snailxr.base.annotation.AutoIncKey;
import com.snailxr.base.task.domain.SeqInfo;
//处理事件监听，需要交由spring管理
public class SaveEventListener extends AbstractMongoEventListener<Object> {
	@Autowired  
    private MongoTemplate mongoTemplate;  
	
	@Override
	public void onBeforeConvert(BeforeConvertEvent<Object> event) {
		final Object source = event.getSource();
		if(source != null){
			ReflectionUtils.doWithFields(source.getClass(), new ReflectionUtils.FieldCallback() {  
		        public void doWith(Field field) throws IllegalArgumentException, IllegalAccessException {  
		            ReflectionUtils.makeAccessible(field);  
		            // 如果字段添加了我们自定义的AutoIncKey注解  
		            if (field.isAnnotationPresent(AutoIncKey.class)) {  
		                // 设置自增ID  
		                field.set(source, getNextId(source.getClass().getSimpleName()));  
		            }  
		        }  
            });  
		}
	} 
    /** 
     * 获取下一个自增ID 
     *  
     * @param collName 
     *            集合（这里用类名，就唯一性来说最好还是存放长类名）名称 
     * @return 序列值 
     */  
    private int getNextId(String collName) {  
        Query query = new Query(Criteria.where("collName").is(collName));  
        Update update = new Update();  
        update.inc("seqId", 1);  
        FindAndModifyOptions options = new FindAndModifyOptions();  
        options.upsert(true);  
        options.returnNew(true);  
        SeqInfo seq = mongoTemplate.findAndModify(query, update, options, SeqInfo.class);  
        return seq.getSeqId();  
    }
	public MongoTemplate getMongo() {
		return mongoTemplate;
	}
	public void setMongo(MongoTemplate mongo) {
		this.mongoTemplate = mongo;
	}
    
}
